Surgical procedures are often used to treat and cure a wide range of diseases, conditions, and injuries. Surgery often requires access to internal tissue through open surgical procedures or endoscopic surgical procedures. The term “endoscopic” refers to all types of minimally invasive surgical procedures including laparoscopic, arthroscopic, natural orifice intraluminal, and natural orifice transluminal procedures.
Endoscopic surgery has numerous advantages compared to traditional open surgical procedures, including reduced trauma, faster recovery, reduced risk of infection, and reduced scarring. Endoscopic surgery is often performed with an insufflatory fluid present within the body cavity, such as carbon dioxide or saline, to provide adequate space to perform the intended surgical procedures. The insufflated cavity is generally under pressure and is sometimes referred to as being in a state of pneumoperitoneum. Surgical access devices are often used to manipulate the patient's internal tissue while maintaining pneumoperitoneum. For example, trocars are often used to provide a port through which endoscopic surgical instruments are passed. Trocars generally have an instrument seal which prevents the insufflatory fluid from escaping while an instrument is positioned in the trocar.
Various surgical instruments can be configured to manipulate tissue during an endoscopic surgical procedure. Some surgical instruments can have a housing or handle portion, an elongate shaft, and an end effector that can be selectively coupled to the shaft and can articulate relative to the shaft. In certain aspects, the device can include one or more modular features, such as having a modular end effector that can be selectively attached to and detached from the shaft. While the modularity of the end effector can improve the device's versatility, the modularity may cause a user to actuate the device improperly. For example, a user may attempt to actuate jaws of the end effector when the end effector is not properly coupled to the shaft such as when the jaws are improperly aligned or if one or more mating features between the end effector and the shaft fail. This can delay the procedure and a user may erroneously believe that the device is damaged and unusable when instead there is an improperly loaded end effector. Still further, during loading of an end effector a closure actuator has to be at a particular angle relative to the device's housing to ensure that the device's components are in the proper position to receive the end effector. Some prior art devices include an external kickstand or latch pivotally connected to a housing such that the latch moves between a locked position and an unlocked position. When the latch is in a locked position, the latch engages a closure actuator to hold the actuator at a particular angle relative to the housing. However, a user may forget to engage the latch prior to beginning loading the end effector onto the shaft and this can lead to an improperly loaded end effector and/or can delay the procedure. It can also be difficult to operate the latch while holding the device and performing other steps of a surgical procedure.
Accordingly, there is a need for endoscopic surgical methods and devices having alternative actuator biasing and locking features.